Mechanical tuning mechanism for a radio set



Aug. 13, 1940. J. H. TEAF MECHANICAL TUNING MECHANISM FOR A RADIO SET Filed April 19, 19:59 2 Sheets-Sheet 1 INVENTOR Jam 12 996 hzfw ATTORNEY Aug. 13, 1940. TEAF 2,211,444

MECHANICAL TUNING MECHANISM FOR A RADIO SET Filed April 19, 1959' 2 Sheets-Sheet 2 0 o o a 1 1/;

za 1/ Z9 Z6 /7 if 29 26 Jf 25f v 9 INVENTOR I Ja2zfl Ta ATTORNEY Patented Aug. 13, 1940 uuirs ATES MECHANICAL TUNING. MECHANISM FOR A RADIO SET John H. 'li'eaf,

Westmon't, N. 'J., assignor, by

mesne assignments, to Condenser Development Corporation, Newark, N. J.,

New Jersey a corporation of Application April 19, 1939, Serial No. 268,702

13 Claims.

This invention relates to a combination radio tuning device, such as a variable condenser, and a manually operable mechanism for selecting the desired station by a single movement of one-of 5 the selectors.

In practically all the mechanical tuning devices heretofore proposed, the tuning device, such as the variable condenser, has been mounted so that-the shaft is parallel with the plane of the panel of the receiving set, requiring a special driving apparatus so that the rotor of the moving tuning element maybe operated by a single knob or button control, and a motion translation device to produce an'indicator movement along the plane of the front panel.

. It is the principal object of my present invention to provide a combination structure in which the movable part of the tuning device is operated by a rotatable shaft through the medium of an operating shaft, both of which are at right angles to the front panel of the set, whereby the operating shaft extends through the pane1 in the usual way and requires only the usual.

turning knob or button for its actuating means.

25 Thus no complicated'mounting is required, but,

on the contrary, a mounting similar to what has heretofore been used with a simple condenserdrive construction may be used.

Another object ofmy invention is .to provide a simple construction of mounting for the combinationmechanism which will have a simple and inexpensive means for mounting an indicator or pointer on the front panel.

These and other objects will be apparent from a reading of the specification, taken in connection with the annexed drawings, wherein:

Figure 1 is a plan view of my combination structure, a condenser being shown as the tuning device, the rotor plates being shown in full mesh with the stator plates.

Figure 2 is a front view of the structure shown in Figure 1. I

Figure 3 is a side elevation looking from left to right of Figure 1. 1

Figure 4 is a view on the line 6-6 of Figure 1.

Figure 5 is a view on the line -5 of Figure 1, but with one of the tuning slides in tuning position. a

Figure 6 is a plan view of one of the slidable manual devices used for setting a given station.

Figure 7 is a view of Figure 6 from the reverse side.

Figure 8 is :a schematic illustration showing the position of the cam member and one of the a two-gang condenser is shown. Since the construction of the condenser per se forms no part of my present invention, the stator units will be merely referred to by the numbers 2 and 3, and the rotors by the numbers 4 and 5. I The'rotor is preferably mounted in the frame I! of the condenser, in accordance with Cramer Patent 1,800,719. A rotatable shaft 6 extends from the rotor of the condenser to a point adjacent the front panel 1 and carries an index finger 8 thereon, which is visible through an opening or transparent member 9 in the front plate. The rotatable shaft 6 carries a gear-wheel m which is preferably one of the anti-back-lash type, and also a pinion l l. The gear-wheel IQ meshes with a pinion 12 carried on a second or operating shaft it which is supported by suitable bearings in the frame members l4 and I5 that, in turn, are anchored to the frame I by a plurality of studs l6 and I1 on one side and I6 and H on the opposite side.

Rotatably but independently mounted on the second -or operating shaft I3, is a cam device having a sleeve l8 and a plurality of cam formations H! which provide cooperative cam surfaces 29 and 2! between them. As shown in the drawings, there are four of these cam formations providing an equal number of cam surfaces 29 and 2|, the purpose of which will be presently pointed out. The cam device also carries a gear 22 preferably of the anti-back-lash typewhich is in mesh with the pinion ll,

Arcuately mounted around theshaft l3 and carried by the framemembers l4 and i5, are a plurality of slidable members, four being indi cated, to correspond to the four cam formations l9. Each 'slidable member includes a flat plate 23 having two lugs 24 and 25 thrown upwardly therefrom. The lug 25 has a clearance hole to receive the smooth reduced and of a threaded member 26, while the lug 24 has a clearance hole for the threaded member 26, having a button or knob 21' on the outer end thereof. Mounted on what may be termed the inner endof the plate l-shaped notch formed by these cam surfaces 23, is a stud 28 which has a groove in its free extremity to receive thehookedendv of a spring 29, while the other end of the spring engages a lug 3d on the frame member l5, the spring acting to hold the plate 23 in what may be termed a retracted position. If necessary, the plate 23 may be provided-with stiffening ribs 3! and 32 which may be fastened thereto in any satisfactory manner as by spot-welding.

Mounted on the reverse side of the plate 23, is a movable member or arm 33 which is pivoted on the same stud 28 to which reference has been made. The outer end of the movable member 33 carries a pin 35 which is adapted to engage the cam surfaces 2!? and 2| as will be later described. Also mounted on the plate 23 is an L-shaped' clamping device, one arm, 35, of which overlaps the end of the movable member 33 adjacent the pin 3d. The other arm 36 of the L- shaped member passes through the opening 31' which is made by forming the lug 2t in the forward end of the plate 23. The plate 23 has oppositely disposed notches therein to receive the outer edges of the arm 36 of the said L- shaped member. Thisend of the arm is also threaded to receive the threaded member 26.

Assuming that it is desired to set one of the slidable units to bring in a given station, the main control knob 38 on the shaft 63 is turned to tune in the desired station. While holding the knob 38 in its tuning position for this station, one of the knobs 2? is turned to loosen the L-shaped clamping member and then the entire slidable member i pushed forwardly so that the pin it carried thereby will engage one of the cam surfaces 2t or 2!, dependent on the position of the cam structure at that time. Since the member 33 has been loosened from under the gripping action of the lever end 35, it is free to take an oscillatory motion about the pivot 28 and the pin at will then slide down one of the set cam surfaces 28 or it until it reaches the bottom of the where it will come to a stop. and the knob 27 is then turned to cause the end 35 of the L-shaped clamping member to move in a direction to tilt the clamp, causing the end 35 thereof to grip the end of the member 33 and lock it in its adjusted position. Then, in the future, when it is desired to tune in this particular station, all that is necessary to be done is to push the button 21, and the pin 36, acting on either the cam surface 26 or 2i, Will cause rotation of the cam member until the pin 34 reaches the bottom of the notch be= tween the surfaces 20 and 2|, as heretofore explained, at which time the station will be brought to its tuning position.

As illustrated in the drawings, the notches forming the cam surfaces 20 and 2| are'so arranged that a forty-five-degree movement of the cam structure is produced when one of the pins 35 moves from the outward extremity of the cam surface 2! as illustrated in-Figure 8, to the position shown in Figure 9, and the gearing ratio between the gears H and I2 is such as to cause the rotor structure to move 180, thereby producing the full range of tuning of the condenser. It is to be understood that as soon as one of the buttons 22 has been pushed to select a station, the button is released and the spring 29 will immediately carry the sliding plate 23 back to its normal inoperative position, whereby a projection 39 on the plate 23 contacts with the frame member i5, thereby acting as a stop for the slide.

While the plates or slides 23 will be carried 2,21 nose I back to their normal position on operation of any other button 2'! or the main control button 38, I prefer to use the springs 29 so as to maintain the buttons 2? in normal inoperative position.

What I claim is:

ll. For a radio receiving set having a tuning device with a movable part for tuning circuits therein, means for operating said movable part of the tuning device including; a rotatable shaft for actuating said movable part of the tuning device, a second shaft operatively connected to the first, means for supporting said second shaft so the same projects through the front panel of the receiving set for actuation therefrom,-a cam device carried on the second shaft and having cam surfaces arcuately positioned around its periphery, slidable members arcuately mounted around the cam device for movement parallel to said shafts and each having a part extending through said front panel, with means on said extending part for moving its slidable member, a member adjustably carried on each slidable member and having an extension for engaging certain cooperative cam surfaces on the cam device for turning it through a predetermined angle corresponding to a radio station, means for presenting the member carrying the extension to cause it to engage its cooperative cam surfaces at a point corresponding to a radio station, a gear-wheel mounted to rotate with the cam device and a pinion on the first-mentioned shaft in mesh with said gear-wheel, for turning said first-mentioned shaft in accordance with the relation between the. extension and its cooperative cam surfaces.

2. For a radio receiving set having a tuning device with a movable part for tuning circuits therein, means for operating said movable part of the tuning device including; a rotatable shaft for actuating said movable part of the tuning device,

asecond shaft geared to the first, means for supporting said second shaft so the same projects through the front panel of the receiving set for actuation therefrom, a cam device carried on the second shaft and-having V-shaped cam surfaces projecting toward the tuning device and being arcuately spaced around the periphery of the cam device, slidable members arcuately mounted around the cam device and in number equal to the number of Vs, outwardly projectinglugs on each slidable membena threaded member carried by said lugs and projecting through the front panel member withan operating member thereon, a member adjustbly carriedon each slidable member and having a pin for engaging the sides of a v cam surface for turning the cam device through a predetermined angle, a clamp carried by each of said threaded members adjacent the ends. of their respective slidable members and having a part overlapping the end of its adjustable member to grip the same when the threaded member is properly set, a gear-wheel mounted to rotate with the cam device and a pinion on the first-mentioned shaft in mesh with said gearwheel, for turning said first-mentioned shaft in accordance'with the relation between a pin and its cooperative cam surfaces.

3. For a radio receiving set having a front panel construction, the combination of a tuning device having a control shaft extending to the front panel and carrying an indicator and a preselecting tuning mechanism disposed between the panel and the tuning device, said mechanism including; frame members, an operating shaft carried by the frame members and extendspaced distances around said operating shaft,-

ing through the front panel with'means for operating it and operatively connected to said con-.

trol shaft, a cam device mounted for independent rotation on said operating shaft and also operatively connected to said control shaft, said cam device having a plurality of cam surfaces arouately-disposed around the cam device, slidable members carried by said frame members arcuately disposed around but spaced from said cam device, each slidable member carrying; a threaded member having one end extending through the front panel with an operating button thereon, an adjustable member having a piece extending into operative relationship to a pair of cam surfaces, and a clamp on the threaded member for clamping the omllatable member in an adjusted position when set by the button.

4. The combination of a tuning device and a preselecting mechanism as set forth in claim 3, further defined in that each slidable member in cludes, a plate carried between two of said frame members, a pair of spaced lugs thrown outwardly from the plate for carrying the threaded member, the adjustable member being a strip attached at one end by a stud to that side of the plate opposite said lugs, while said clamp has an arm extending through a slot in the plate and overlying the end of said adjustable member.

5. The combination of a tuning device and a preselecting mechanism as set forth in claim 3, further defined in that each slidable member includes, a plate carried between two of said frame members, a pair of spaced lugs thrown outwardly from the plate for carrying the threadedmemher, the adjustable member being a strip attached at one end by a stud to that side of the plate opposite said lugs, while said clamp has an arm extending through a slot in the plate and overlying the end of said adjustable member, said stud having a portion extending on the lug side of the plate, and a spring attached to this end of the stud and to one of the frame members for returning the slidable member to normal position after a tuning operation by said button.

6. The combination of a tuning device and a preselecting mechanism as set forth in claim 3, further defined in that the cam device is cupshaped and has V-shaped notches extending from its edge toward its base, the number of notches corresponding to the number of radio stations that is desired to be selected by merely pushing a button on said threaded members, the pins on said adjustable members projecting into the V notches as and for the purposes described.

7. The combination of a tuning device and a prelecting mechanism as set forth in claim 3, further defined in that the two shafts and the axis of the slldable member are substantially parallel and all at right angles to the panel, whereby the complication of mounting the apparatus in a set is reduced to a minimum.

8. For a radio receiving set, the combination of a timing condenser having a rotor with a control shaft and a selecting mechanism for turning the shaft a predetermined amount corresponding to the radio stations desired to be selected, said mechanism including; a frame carrying a hand-operated shaft geared to the control shaft for direct action thereof, a plurality of slid- 7 able units carried by the frame at arcuately each unit coorresponding to a radio station desired, each slidable unit comprising a plate carrying on one side a threaded member having an end equipped with a push-button, and on the other side an arcuately adjustable lever carrying a pin extending toward the operating shaft, a clamp operated by said threaded member for clamping said lever, and a cam device independently rotatable on the operating shaft and having a pair of cam surfaces for each pin positioned so as to be engaged by the pinwhena slidable member is actuated and interconnecting means between said cam device and the control shaft.

9. The combination of a tuning condenser and selecting mechanism as set forth in claim 8, further defined in that'said clamp is L-shaped with the threaded member going through one arm of the L, while the other arm of the L passes through a slot in the plate and engages the end of the lever carrying the pin.

10. The combination of a tuning condenser and selecting mechanism as set forth in claim 8, further defined in that said cam device has V- shaped notches forming cam surfaces for each pin, thereby providing a reverse direction ofthe cam device and control shaft, depending on which side of the V the pin engages.

11. The combination of a tuning condenser and selecting mechanism as set forth in claim 8, further defined in that said cam device is cupshaped, with V-shaped notches equally spaced around and in the side-walls, the number of notches corresponding to the number of stations desired to be under push-button control.

12. The combination of a tuning condenser and selecting mechanism as set forth in claim 8, further defined in that said cam device has a cylindrical wall with V-shaped notches in one end and arcuately spaced there-around, and further defined in that the interconnecting means between the cam device and the control shaft is a pair of gears, the ratio being such, together with the depth and angle of the V, that the movement of a pin along the entire side of a V cam surface will move the control shaft and condenser rotor through its full tuning range.

13. In a radio receiving set, the combination of a movable tuning element having a control shaft extending to the front panel of the set and carrying an indicator adjacent a viewing space in the panel, and a manual tuning mechanism comprising an operating shaft extending parallel to said control shaft and drivingly connected thereto, a plurality of arcuately arranged manually slidable members each associated with a wave-length, a cam device positioned within the confines of said slidable members and having separate and individual cam surfaces around its periphery, one for each slidablemember and each adapted to be engaged only by parts of its associated slidable member, a driving connection between the cam device and the control shaft, and means associated with each'slidable member for adjusting said parts which engage its cooperative cam surfaces for determining the position to which the tuning element will move when the sliding member is operated.

JOHN H. TEAF.

CERTIFICATE. OF CORREGTION.' I enema No. 2,211,1 M. August 15, 191 0.

- 1 JOHN It is hereby certified that; error' eppears in the prinfied specification of the above nuz nbered patent requiring correction as follows: Page 2, firs column, line 1 5, for the reference numeral "35" read "56"; and that the said Letters Patent should be reed'with thi s cerrectien therein that the seme may conform to therecord otf'the case hi the Patient Office.

Signed and sealed this 21;.th day of September, A. D. 1914.0.

Henry Ven' Arsdele, (Seal) Acting cemmissiener of Patents. 

